Use of Bioimpedance to Assess Changes in Hemodynamics During Acute Administration of CPAP.

Background: Attempts to investigate the mechanisms by which continuous positive airway pressure (CPAP) therapy improves heart function in patients with obstructive sleep apnea (OSA) have been limited by the lack of non-invasive methods to assess cardiac performance. We used transthoracic electrical bioimpedance (TEB) to assess acute hemodynamic changes including heart rate (HR), stroke volume (SV), cardiac output (CO) and cardiac index (CI) during PAP titration in (1) post-operative cardiac surgery patients, (2) patients with severe OSA, and (3) normal healthy volunteers.

Methods: Post-operative cardiac surgery patients were studied via TEB and pulmonary artery catheter (PAC) during acute titration of positive end-expiratory pressure (PEEP) while mechanically ventilated.

Anomalous right coronary artery: a multimodality hunt for the origin.

Anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is a rare congenital anomaly. Although there have been several cases of ARCAPA reported in the literature, we present a case which highlights the challenges of diagnosing this rare condition and the incremental value of using multiple imaging modalities. A healthy 48 year old female presented with angina and exertional shortness of breath.

Primary cardiac diffuse large B cell lymphoma presenting with superior vena cava syndrome.

Primary cardiac lymphomas are rare extranodal lymphomas that should be distinguished from secondary cardiac involvement by disseminated non-Hodgkin's lymphoma. Cardiac lymphomas often mimic other cardiac neoplasms, including myxomas and angiosarcomas, and often require multimodality cardiac imaging, in combination with endomyocardial biopsy, excisional biopsy or pericardial fluid cytology, to establish a definitive diagnosis. A 60-year-old immunocompetent man who presented with superior vena cava syndrome secondary to a right atrial, primary cardiac diffuse large B cell lymphoma (non-Hodgkin's lymphoma) is described in the present article.

Primary cardiac lymphoma: molecular cytogenetic characterization of a rare entity.

Background: The majority of cardiac atrial neoplasms represent benign myxomas. Rarely, malignant cardiac neoplasms are encountered and can include primary cardiac neoplasms, as well as secondary tumors involving the heart. As many cardiac neoplasms lack pathognomonic clinical features, histopathologic diagnosis is crucial for classification and appropriate treatment of these neoplasms.

Heart rate variability following coronary artery bypass graft surgery as a function of recovery time, posture, and exercise.

This study examined the claim made by Niemela et al. (1992) that the decline in heart rate variability after coronary artery bypass graft surgery is irreversible. We tested six women and 16 men six and 12 weeks postoperative in three postures: in the supine position, in the standing position, and during low-intensity steady-state exercise.

Spontaneous baroreflex sensitivity after coronary artery bypass graft surgery as a function of gender and age.

The effects of coronary artery bypass graft (CABG) surgery on spontaneous baroreflex (SBR) sensitivity and heart rate variability were examined in 11 women and 23 men preoperatively and 5 days postoperatively. Electrocardiograph R-R interval and beat-by-beat arterial blood pressure data were collected continuously for 20 min in the supine and standing postures. Coarse graining spectral analysis was performed on the heart rate variability data.

Cardiac troponin I is modified in the myocardium of bypass patients.

Background: Selective proteolysis of cardiac troponin I (cTnI) is a proposed mechanism of contractile dysfunction in stunned myocardium, and the presence of cTnI degradation products in serum may reflect the functional state of the remaining viable myocardium. However, recent swine and canine studies have not demonstrated stunning-dependent cTnI degradation.

Methods And Results: To address the universality of cTnI modification, myocardial biopsy samples were obtained from coronary artery bypass patients (n=37) before and 10 minutes after removal of cross-clamp.

Modified Bentall technique for aortic root replacement: a simplified approach to the short left coronary artery.

The short left coronary artery encountered during aortic root replacement with the modified Bentall (coronary button) technique may pose a significant problem for the surgeon. A simple solution entails the placement of a short interposition Dacron graft between the native coronary artery and the aortic graft. This approach has been successfully employed in 2 patients.

Aortic dissection and use of the nicotine patch: a case involving a temporal relationship.

A 33-year-old woman presented with chest and abdominal pain shortly after first and second applications of the nicotine patch. Type A aortic dissection was diagnosed and repaired. Pathological examination revealed cystic medial necrosis, subacute and acute dissection, with no evidence of chronic aortic insufficiency.

Frequency content and sex difference of the Frank lead signal-averaged ECG in a population with significant coronary artery disease. Comparison with concurrent 12-lead ECG morphology.

The 12-lead electrocardiogram (ECG) and a 100-beat signal-averaged Frank lead ECG (SAECG) at a sampling rate of 1,000 Hz and with 16-bit resolution were recorded from 52 women and 256 men with significant coronary artery disease presenting for coronary artery revascularization. The QRS portion of each Frank lead was digitally filtered in four bandwidths: 0-10, 10-60, 60-150, and 150-250 Hz. The root-mean-square (RMS) voltage of each filtered signal was calculated as an absolute value and normalized as a percentage of the sum of the four filters, creating 27 variables.

Salvage of ischemic myocardium by nonsynchronized retroperfusion in the pig.

Salvage of ischemic myocardium, with the aid of a nonsynchronized coronary sinus retroperfusion system, was studied in a pig infarct model. In anesthetized open chested animals, the left anterior descending coronary artery was occluded for 4 hours and then reperfused for 1 hour before the animals were killed. In the control group (n = 12) no therapy was used.

Aortic valve replacement with stentless porcine bioprostheses.

Aortic valve replacement with stentless porcine valve should provide superior hemodynamic results to stented porcine valve because the obstruction caused by the stent and the sewing ring is eliminated. In addition, the coronary sinuses of the recipient may allow for better dissipation of the mechanical stress to which the leaflets are subjected during diastole, thus enhancing durability of the heterograft. Aortic valve replacement with stentless glutaraldehyde-fixed aortic porcine bioprosthesis was carried out successfully in six young sheep.

Reconstruction of the left ventricle with autologous pericardium.

Autologous pericardium was used to reconstruct different parts of the left ventricle in 25 desperately ill patients. Fourteen patients had intractable sepsis resulting from infective endocarditis and myocardial abscess and 10 patients had noninfectious disorders. Of the patients with infections, 12 had valvular endocarditis with periannular abscess and three had interventricular septal abscess.

Ascending aorta to bifemoral bypass--a ventral aorta.

In the decade since April 1975 we accumulated a series of 18 patients with arterial conduits from the ascending aorta to the femoral arteries, 10 men aged 53 to 75 years (mean, 60 years) and eight women aged 33 to 56 years (mean, 50 years). In the first two patients, the conduit was placed subcutaneously; in the remaining 16 patients, it was placed behind the rectus muscle and in front of the posterior rectus fascia, thus following the ventral anastomotic axis of the internal mammary and inferior epigastric arteries. The conduit is not visible, palpable, or compressible in this position.

Intermittent percutaneous infusion into the hepatic artery of cytotoxic drugs for hepatic tumours.

Between June 1, 1976 and Apr. 30, 1981, 157 patients were treated for inoperable cancer of the liver by intermittent percutaneous infusion of chemotherapeutic agents into the hepatic artery. The majority of these patients had metastatic colorectal cancer.